C/2007 N3 (Lulin) - JAN 28, 2009

After making some other early morning observations on January 28, 2009, I turned the telescope on Comet Lulin. Astronomical twilight was threatening, and I needed to move quickly. The view was much better than earlier in the month. The coma appeared brighter and larger and both ion and dust tails appeared longer. The dust tail appeared to be about 12 arc minutes in length at a PA of 100°. It also appeared heavier on its southern side. The ion tail was still more difficult and appeared to be about 8 arc minutes in length at a PA of 280°. The coma took an elongated appearance, stretching in the direction of the two opposing tails. It was very slightly tinted green. The pseudo-nucleus appeared as a thicker knot of brightness at the center and I would rate the degree of condensation as 6.

I took a couple minutes to attempt a more attentive magnitude estimate. With my 32 mm Plössl, I defocused at low power and compared it to a couple nearby stars. The comet appeared brighter than HIP 75532 (vMag 7.74) and fainter than 28 Librae (vMag 6.15). It was a bit closer to 28 Librae in magnitude, so I would estimate the comet at 6.8 magnitude. That's a significant difference from my rough estimate earlier in the month, but it still makes for a great, bright telescopic comet.

If you are observing the comet with a telescope under skies that are even slightly compromised, the tails will likely be very difficult to see. Under excellent conditions at Sunset Crater National Monument this morning, they were still very subtle. The coma, however, is readily visible and should still provide a nice view of the comet even if the tails don't show up. I'm still looking forward to its appearance at opposition in February when it will swing by at a reasonable hour of the night. Check The Skyhound Site for a current finder chart and be sure to look this comet up!

[NOTE: Sketches, a photograph, and detailed report of my February 20, 2009, observation of this spectacular comet can be found here: C/2007 N3 (Lulin) FEB 20, 2009.

6 Comments

As usual, very nice sketch! It is certainly easier to portray the tails in a sketch than in a photo. I shot the comet from my driveway with both CCD and DSLR, the tails are visible, but very faint in the photos.

Unfortunately local streetlights precluded dark adaptation and I didn't even try to observe visually. Will probably try that later in the month. On the other hand I have had good opportunity to hit 144P Kushida under dark skies.

Hi Andrew, I just caught the Night of Comets post at your site. Great work on those images! I can't wait to see the shot of Lulin. And yeah, the relative brightness of the tails to the coma in my sketch is probably a bit like viewing them on a logarithmic scale...the difference looks pretty gradual here, but is quite huge when looking at it live.

Another observer, Rony DeLaet is not quite as hesitant as I am about keeping faint structures extremely subtle in his digital sketches--you need to observe them in a darkened room, and sometimes use averted vision to appreciate the sketch. His are some of the most realistically crafted, true-to-life sketches I have seen. I hope you get a chance to observe it under dark, transparent skies of a volcanic slope soon.

my location is Cuernavaca, Morelos, Mexico. This morning (Feb 6) at 6 am local, I saw Lulin close to Alpha Libra, but not exactly as indicated on predictions: not yet arriving there, moving from Scorpio. It is not easy to observe with the bare eye: impossible to watch straight, I had to view it with the corner of my eyes...almost guessing! An extremely faint small cloud...I observed the sky and tryed to see a nebulous small spec: when located in Libra top triangle, I checked with Sky & Telescope charts...and yes, that was it.

Extremely cold morning (for Cuernavaca...) & extremely clear, with no light pollution were I live (north of the city). Mercury, that elusive planet, was clear and high above the eastern horizon, Mars was behind the morning glare & unobservable. The Southern Cross was low on south horizon. At the begining of my observation, a shooting star went by...Blau (our siamese) and Iván (our labrador) were my company for viewing our Kosmos this morning, surrounded by my garden plants. The most beautifull spring dawn!

Wonderful report, DonYan! Thanks very much for sharing the view you had. I haven't tried observing it with the naked eye yet. I did have a look at it with 15x70 binoculars on Friday morning (Jan 6) while making an overnight drive through western Oklahoma. It was paired beautifully with the brilliant double, Alpha Librae and was very slightly elongated to the east. No time for a sketch though. I hope you get more opportunities to observe it as it moves westward.

I think an 8 inch scope is a great way to go. I haven't observed through an 8 inch Discovery that I can recall, but you may want to check Cloudy Nights and search the forums for "Discovery 8 inch" and see any comments made.

I have a sketch of M13 made with my 6 inch Newtonian. I haven't made a detailed observation of it with the 8 inch, but it would certainly resolve more stars and look great. For comparison, here is a sketch of M3 made with the 8 inch. Averted vision revealed a sparkling cloud of stars across the periphery, and a full, granular texture across the surface.